1. Priority Claim
This application claims the benefit of priority from European Patent Application No. 11 450 137.2, filed Nov. 4, 2011, which is incorporated by reference.
2. Technical Field
The invention relates to filter systems for microphones.
3. Related Art
In general, a distinction can be made between passive and active microphones, with dynamic microphones belonging to the passive microphone group and condenser and electret microphones belonging to the active microphone group, for example, condenser microphones and electret microphones, also called electrostatic microphones, may be used in a recording area and may use a supply voltage that may be provided by a connected device, such as a mixer or an effects unit. In condenser microphones, a supply may provide polarization voltage for electrodes of a microphone capsule and an operating voltage for an associated microphone amplifier. In electret microphones, a supply may provide an operating voltage for the microphone amplifier, since the polarization voltage may be provided by a charged Teflon coating.
In contrast, dynamic microphones may not use an external power supply, because such microphones may use direct conversion of sound vibrations into an electrical voltage. Because of this direct conversion, dynamic microphones may be useful for live concerts and on-stage use, for example.
Nevertheless, with this benefit, there are tradeoffs. For example, with dynamic microphones quality of sound output may depend on electrical impedance of downstream devices.